Bio-activated oral care instrument

ABSTRACT

An oral care instrument, such as a motorized toothbrush, which activates upon exposure to the oral environment of the user, is described. The electrical conductivity of saliva, optionally mixed with toothpaste and water, may be utilized to complete an electrical circuit that powers a motorized device within the instrument.

CROSS-REFERENCE TO RELATED APPLICATION

The present application is a divisional of U.S. patent application Ser.No. 11/866,078, filed on Oct. 2, 2007, the contents of which areincorporated herein by reference.

FIELD OF THE INVENTION

The present invention pertains to an oral care instrument, such as amotorized toothbrush, which activates upon exposure to the oralenvironment of the user.

BACKGROUND OF THE INVENTION

Powered oral care instruments such as electric, motorized toothbrushesused to clean teeth are well known. Typically these toothbrushes employvibrating or rotating motion, or a combination of motions, to effectuatetooth cleaning, whitening, and/or repair. Toothbrushes may also includea motorized activator, such as a pump, for dispensing active agents toone or more outlets.

A feature commonly found on electric toothbrushes and other oral careinstruments is an on/off switch or button which may be shifted ordepressed to electrically activate or deactivate the instrument.

In the case of an electric toothbrush, for example, activationestablishes an electrical circuit which causes movement of the bristlesfor contacting tooth and soft tissue surfaces, or dispensing of anactive agent. The switch is typically located on or near the handleportion of the toothbrush. The primary feature of such a switch is thatit remains either in the “on” position or the “off” position until theuser manually changes it. The toothbrush motor can be engaged oractivated prior to the brush head being placed in the mouth, or the usercan wait until the brush head is placed within the mouth beforeactivating the motor.

It would be desirable to provide a toothbrush that reduces or overcomessome or all of the difficulties inherent in prior known toothbrushes.Particular objects and advantages will be apparent to those skilled inthe art, that is, those who are knowledgeable or experienced in thisfield of technology, in view of the following disclosure of theinvention and detailed description of certain embodiments.

SUMMARY

Aspects of the present invention advantageously exploit particularconditions which are present in the mouth, either continually or atdiscreet instances during oral care or treatment. The electricalconductivity of saliva, optionally mixed with toothpaste and water, maybe utilized to activate or complete an electrical circuit that powersthe instrument. The existence of one or more such conditions provides abasis for automatic functioning of the oral care instrument when aportion (e.g., the head, or the head and neck) is placed into the mouthand the condition, or a combination of conditions, is/are detected.

In accordance with one aspect, a motorized toothbrush includes a headcarrying cleaning elements and a handle configured to connect to a powersource. A motorized device is activated upon exposure of the toothbrushto an electrolyte solution.

In accordance with another aspect, a motorized toothbrush includes ahead carrying cleaning elements, a handle including a cavity, and apower source received in the cavity of the handle. A motorized device isoperably connected to the power source and operably connected to thehead. Electrical conducting elements are operably connected to the powersource and the motorized device. The motorized device is activated uponexposure of the electrical conducting elements to an electrolytesolution.

In accordance with a further aspect, a motorized toothbrush includes ahead carrying cleaning elements, a handle, and a power source containedwithin the handle. A motorized device is operably connected to the powersource and operably connected to the head. Electrical conductingelements are operably connected to the power source and the motorizeddevice. A switch is operably connected to at least one of the electricalconducting elements and the power source. The motorized device isactivated upon exposure of the electrical conducting elements to anelectrolyte solution having a threshold conductivity.

These and other aspects of the invention are apparent from the followingdetailed description of certain embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings should be understood to present an illustration of variousaspects of the invention and/or principles involved, and not to limitthe scope of the subject matter as set forth in the appended claims.

FIG. 1 depicts a representative oral care instrument, a toothbrush,illustrating various aspects of the invention.

FIG. 2 depicts an alternative embodiment of a toothbrush illustratingvarious aspects of the invention.

FIG. 3 depicts another alternative embodiment of a toothbrushillustrating various aspects of the invention.

FIG. 4 depicts yet another alternative embodiment of a toothbrushillustrating various aspects of the invention.

DETAILED DESCRIPTION OF CERTAIN PREFERRED EMBODIMENTS

The present invention relates to a bio-active oral care instrument,having the ability to operate automatically, when the instrument or aportion thereof is exposed to one or more conditions, such as theambient electrical conductivity, existing in the oral environment. Otherconditions and combinations of conditions, such as pH, temperature,solute concentrations, etc. could likewise be detected and used as thebasis for automatic operation. Furthermore, aspects of the invention areillustrated in the remainder of this disclosure with reference to anelectric motorized toothbrush, although it is understood that theoperation of any number of oral care instruments, together with theassociated advantageous features and/or beneficial effects describedherein, could likewise be achieved. Other oral care instruments, forexample, include those used in dental drilling, polishing, and grinding;oral suction instruments, oral surgical instruments; and otherinstruments used in the oral cavity which are powered by motorizeddevices and especially electrical devices.

The representative toothbrush illustrated in FIG. 1 has a handle 1 and ahead 5 carrying one or more cleaning elements, which are depicted inFIG. 1 as a plurality of bristles 6. Also illustrated is a neck 4located between, and connecting, handle 1 and head 5. The bristles 6, asshown, form clusters that are anchored to the head 5 and provide aprofiled brushing surface with their free ends. Other bristleconfigurations are of course possible, as well as removable/exchangeablebristle clusters. Different types of cleaning elements (e.g.,elastomeric wipers, nodules, pointed structures, etc.) may also becarried on head 5 instead of, or in addition to, bristles.

The neck 4 is provided with electrical conducting elements 7 (e.g., ananode and a cathode) that are exposed to the exterior surface of thetoothbrush. In other embodiments, the electrical conducting elements 7can be located on the head 5, for example on the surface opposite thatwhich carries bristles 6 (see e.g., FIGS. 3-4). The use of electricalconducting elements 7 on different parts of the toothbrush is alsopossible. A plurality of electrical conducting elements 7 can also beincorporated in various positions to activate the instrument in theevent that sufficient electrical conductivity is established between anygiven pair(s) of electrical conducting elements 7 located at any desiredposition. Integrated in the region of the neck 4 which is adjacent tothe head 5 is a motorized device 11 such as a mechanical vibratorydevice. Motorized device 11 is operably connected to head 5 such thatvibrations or other movement produced by motorized device 11 may beimparted to the head 5 and/or the bristles 6 to effect or enhance theteeth-cleaning or teeth-whitening action. The motorized device 11 isoperably connected, via electrical connections 34 in the neck 4 to apower source (e.g., a battery, not shown), which may be accommodated inthe handle 1. Operably connected and operably connectable refer to theability of the electrical connections, or other elements, to readilyform an electrical circuit (e.g., when a switch is depressed or when apower source is connected or installed). Operably connected and operablyconnectable may also refer to the ability of mechanical components to beconnected to one another in such a manner as to allow or provide forphysical movement of one or more elements. The motorized device may bealternatively incorporated in the head 5 or handle 1 of the toothbrush.In representative embodiments, electrical connections 34 may be metalwire or electrically conductive plastic tracks.

In a particular embodiment where motorized device 11 is a vibratorydevice, it will have a vibratory element which can be in the form of aneccentric, which produces mechanical vibrations and can be rotated aboutan axis located in the longitudinal direction of the toothbrush.Alternatively, instead of an eccentric which can be driven in rotation,it would also be possible to have a vibratory element which can bedriven in a translational manner. Otherwise, the bristle-carrying head 5can be arranged such that it can be moved in relation to the neck 4 inorder for the latter, in the case of vibrations produced by motorizeddevice 11, to move in relation to the rest of the toothbrush.

As shown, also accommodated in the handle 1 is a sheath or sleeve 20which extends in the longitudinal direction of the handle 1 and is madeof electrically conductive material. In the representative embodimentshown, both the handle 1 and the sleeve 20 are open to the rear, thusforming a cavity 21 which can be closed from the rear by a closure part22 and into which it is possible to insert a battery, such as acommercially available, non-rechargeable cylindrical battery, with adefined voltage (e.g. 1.5 V), as the power or voltage source formotorized device 11. It would also be possible, however, for a buttoncell or for a rechargeable storage battery to be used as the powersource. An external power source such as a conventional electricaloutlet or a combination of voltage sources may be employed as the powersource.

Also shown in the particular illustrative embodiment of FIG. 1 is aspring contact 29 for a positive pole of a battery (not shown), which isfitted in the sleeve 20, on a transverse wall 28, and is electricallyconnected to the motorized device 11 through the electrical connections34 and switch 32, which is installed in the sleeve 20 and can beactuated from the outside of the handle 1. Switch 32 may also be, forexample, a magnetic switch pulse switch or a pulse switch arranged on aprinted circuit board with further electronic components that store theswitching state. In other embodiments, closure part 22 can itself act asa switch, such that electrical contact between the power source andmotorized device 11 is established or interrupted by turning closurepart 22 to alter the position of contact surface 22 b relative to thenegative pole of a battery.

It is to be appreciated, as discussed in greater detail below, thatswitch 32 is not necessary due to the ability of the toothbrush to turnon automatically when in the user's mouth. In some embodiments,therefore, the toothbrush can be “switchless” or “buttonless.”

Switch 32 may be depressed or adjusted by the user to effect a number ofoperating modes. For example, in “on” and “off” positions or settings,electrical communication or an electrical circuit between the powersource and motorized device 11 may be continually established orcontinually interrupted, respectively. In the former case, for example,the electrical conducting elements 7 may be bypassed to allow continuousoperation of motorized device 11, regardless of the presence of aconductive medium between electrical conducting elements 7. Switch 32may also have a position corresponding to conditional completion of theelectrical circuit.

Also as shown in FIG. 1, the closure part 22 is provided with a threadedstub 22 a made of an electrically conductive material, which may be thesame material (e.g., a metal such as copper or a conductive plastic)used for the electrical conducting elements 7, electrical connections34, spring contact 29, and/or sleeve 20. Closure part 22 can be screwedinto the handle 1 and/or into the sleeve 20 by way of said threaded stub22 a. The threaded stub 22 a is provided with a contact surface 22 bwhich, with the closure part 22 screwed in, comes into abutment againstthe negative pole of a battery (not shown) when inserted into the sleeve20. During operation of the motorized toothbrush, this negative pole iselectrically connected to motorized device 11 via the threaded stub 22a, the sleeve 20 itself, and electrical connections 34 connecting sleeve20 to motorized device 11. It would also be possible, instead of throughthe use of sleeve 20, for the power from the negative pole to betransmitted in some other way, for example using wires or electricallyconductive plastic tracks. Instead of the rear closure part 22 beingscrewed to the handle 1, it would, of course, also be possible to havesome other type of releasable connection (e.g. plug-in connection,bayonet connection, etc.) and a corresponding configuration of thecontact part interacting with the negative pole of the battery.

One representative characteristic of the oral environment which differssignificantly from the surrounding or ambient “non-use” environment iselectrical conductivity, which increases directionally with theconcentration of electrolytes in the surrounding medium (e.g., saliva).In some embodiments, this “non-use” environment may even include rinsingor submersing the portion of the instrument that is normally placed inthe mouth (e.g., the head 5 of the toothbrush) in water (e.g., forpre-wetting or rinsing purposes), since the electrical conductivity ofsaliva is higher than that of water. This difference can thus beutilized to allow the instrument to “detect” when it is being used andthereby operate in an automatic mode.

Additionally, the combination of water, saliva, and dentifrice (e.g.,toothpaste or other ingredient) that is generated in the mouth duringuse of the instrument often affords even a significantly higherelectrical conductivity than saliva alone. This is due to the generationof ions, often in large concentrations, from typical oral care products,including tooth fluoridating, whitening, and/or remineralizationproducts which contain or form aqueous cations, such as sodium (Na⁺),potassium (K⁺), calcium (Ca⁺²), magnesium (Mg⁺²), iron (Fe+³), etc. andanions, such as phosphate (PO₄ ⁻³), diphosphate (P₂O₇ ⁻⁴), carbonate(CO₃ ⁻²), fluoride (F⁻), chloride (Cl⁻), etc.

In view of the above, the increase in electrical conductivitysurrounding a portion of the toothbrush, e.g., head 5 or head 5 and neck4, when placed in the mouth, can be used to complete an electricalcircuit, together with an electrical power or voltage source such as anexternal electrical outlet or an internal battery to activate motorizeddevice 11, causing movement of head 5.

In an “auto” position or setting, motorized device 11 is powered by thepower source only in the event that sufficient electrical conductivity(e.g., a threshold level of conductivity, or sufficiently lowresistance) exists between electrical conducting elements 7 in the neck4. The required electrical conductivity, as needed for the “conditionalcompletion” of the electrical circuit to power motorized device 11, maybe provided, for example, by an electrolyte solution containing ions(e.g., calcium, phosphate, fluoride, or peroxide ions) such as thatgenerated from a combination of saliva, water, and toothpaste existingin the oral environment during use. When the electrical conductivitybetween conducting elements 7 is no longer present, the electricalcircuit is incomplete, thereby deactivating motorized device 11. Thus,in an “auto” or automatic operating mode, motorized device 11 will notbe activated when the toothbrush is stored since air is the mediumbetween electrical conducting elements 7. According to some embodiments,when the brush is being rinsed outside the mouth, the water betweenelectrical conducting elements 7 will not have sufficient electricalconductivity to activate motorized device 11.

According to some embodiments of the invention, it may be desired torequire that the electrolyte solution (e.g., saliva or awater/saliva/toothpaste mixture), to which the toothbrush is exposedduring use, have a threshold (or minimum) level of conductivity beforemotorized device 11 is activated. This threshold level of conductivity,for example, may be based on a threshold (or minimum) current needed toactivate motorized device 11. This threshold conductivity, required toautomatically turn on the toothbrush, may be associated with theelectrical conductivity of saliva alone or an electrolyte solutionhaving a relatively higher conductivity (e.g., an aqueous solution oftoothpaste) or lower (e.g., a mixture of saliva and water) conductivity.For example, the threshold conductivity may be associated with astandard or model electrolyte solution designed to mimic the electricalconductivity of saliva having one or more specified, additionalconcentrations of dissolved ions such as calcium, phosphate, fluoride,peroxide, and other ions or mixtures of ions.

In this manner, the automatic functioning of the oral care instrumentcan be made more or less sensitive to the particular conditions orconditions associated with the environment in which the instrument isused (i.e., the “use” condition(s) required to activate the instrument).It is also possible that the sensitivity of the instrument can beadjusted by, set by, or tailored to, the user (e.g., to avoid eitheractivation of the instrument during “non-use” conditions ornon-activation during “use” conditions) and thereby ensure effectivefunctioning of the instrument in automatic mode.

In certain embodiments, the change in conductivity of the medium betweenelectrical conducting elements 7 is measured by a sensing device 38,such as a circuit board 38 or other suitable sensing device, connectedto electrical conducting elements 7 by electrical connections 40. Incertain embodiments, sensing device 38 may measure the drop inresistance between conducting elements 7. When the conductivity changereaches a preset value as detected by sensing device 38, switch 32 maybe activated so as to complete the electrical circuit to power motorizeddevice 11. In such an embodiment, the electrical circuit need notinclude the electrolyte solution between conducting elements 7. That is,the electrolyte solution is used as a trigger to activate switch 32 byway of sensing device 38, but does not actually form part of theelectrical circuit that powers motorized device 11.

In other embodiments, switch 32 could be activated based on thedifferential change in conductivity between conducting elements 7. It isto be appreciated that the level of electrolyte in the medium will varyfrom person to person, and/or may vary based on the formula of the oralcare solution used. In such embodiments, these variations will notaffect the current level delivered to the motor. Thus, for example, whenusing a sensitivity type toothpaste product having 5% KNO₃, thetoothbrush would not operate differently than when used with a standardtoothpaste product having a lower ionic strength.

According to other embodiments, when exposed to a solution with athreshold level of electrical conductivity, motorized device 11 and,therefore, the dental instrument itself may be set or adjusted (e.g.,using a timer) to activate for a minimum duration (e.g., a typicalbrushing duration such as about 1 minute to about 5 minutes). Thisensures that the toothbrush or other instrument will function for atleast enough time to effectively accomplish a given task (e.g., toothcleaning and/or whitening). This also promotes continuous operation,even if contact between the instrument and the electrolyte solution istemporarily lost, for example, when a toothbrush is temporarily removedfrom the mouth during brushing. The minimum duration for activation ofthe dental instrument (e.g., two minutes) may be fixed or may otherwisebe set or adjusted according to a user's preferences.

As discussed above, the ability of a dental instrument to “activate”(e.g., to turn on a motor) when exposed to the environment in which itis used (e.g., an electrolyte solution in the mouth) can obviate theneed for an “on/off” switch or button, creating a simplified operation.

Another embodiment of a motorized device activated when conductingelements 7 are exposed to an electrolyte solution is shown in FIG. 2. Areservoir 44 is provided in handle 1 for storing an active agent.Conducting elements 7 are used to activate a pump 46, which causes apredetermined quantity of the active agent to be delivered fromreservoir 44 through a channel 48 leading to a plurality of outlets 50located in head 5. An exemplary delivery system for an active agent isdescribed in copending application Ser. No. 11/457,086, the entiredisclosure of which is incorporated herein. Other examples of motorizeddevices that can be activated upon exposure of conducting elements 7 toan electrolyte solution will become readily apparent to those skilled inthe art, given the benefit of this disclosure.

In view of the above, it will be seen that several advantages may beachieved and other advantageous results may be obtained. As variouschanges could be made in the above oral care instruments withoutdeparting from the scope of the present disclosure, it is intended thatall matter contained in this application shall be interpreted asillustrative only and not limiting in any way the scope of the appendedclaims.

1. A motorized toothbrush comprising: a head carrying cleaning elements;a handle configured to connect to a power source; a motorized devicethat is activated upon exposure of the toothbrush to an electrolytesolution.
 2. The toothbrush of claim 1, wherein the motorized devicecauses movement of the head.
 3. The toothbrush of claim 1, wherein theelectrolyte solution completes an electrical circuit with a powersource.
 4. The toothbrush of claim 1, further comprising electricalconnections operably connected to the motorized device.
 5. Thetoothbrush of claim 4, further comprising a power source, the electricalconnections being operably connectable to the power source.
 6. Thetoothbrush of claim 1, wherein the motorized device activates and causesvibration or rotation of the cleaning elements, upon exposure of thetoothbrush to the electrolyte solution.
 7. The toothbrush of claim 1,wherein the toothbrush is switchless or buttonless.
 8. The toothbrush ofclaim 1, further comprising electrical conducting elements exposed to anexterior surface of the toothbrush at either the head or a neck that islocated between the handle and the head.
 9. The toothbrush of claim 8,further comprising electrical connections operably connected to themotorized device, and a switch operably connected to at least one of theelectrical connections and the electrical conducting elements to preventelectrical communication between the power source and the motorizeddevice or to complete the electrical circuit even without exposure ofthe head or neck to the electrolyte solution.
 10. The toothbrush ofclaim 9, wherein the switch has at least three settings associated withinterruption of the electrical circuit, completion of the electricalcircuit, and conditional completion of the electrical circuit uponexposure of the toothbrush to the electrolyte solution.
 11. Thetoothbrush of claim 8, further comprising a sensing device operablyconnected to the electrical conducting elements.
 12. The toothbrush ofclaim 11, wherein the sensing device measures conductance between theelectrical conducting elements.
 13. The toothbrush of claim 1, whereinthe motorized device activates upon exposure of the toothbrush to athreshold conductivity of the electrolyte solution.
 14. The toothbrushof claim 11, wherein the threshold conductivity is based on theconductivity of saliva.
 15. The toothbrush of claim 14, wherein thethreshold conductivity is based on the conductivity of saliva having oneor more additional amounts of dissolved ions selected from the groupconsisting of calcium, phosphate, fluoride, peroxide, and mixturesthereof.
 16. The toothbrush of claim 1, wherein the motorized deviceactivates for a minimum predetermined duration upon exposure of thetoothbrush to the electrolyte solution.
 17. The toothbrush of claim 1,wherein the handle includes a cavity and further comprising a batteryinsertable into the cavity.
 18. The toothbrush of claim 17, wherein thecavity contains an electrically conductive sleeve which is open to therear and closeable by a rear cover.
 19. The toothbrush of claim 1,further comprising a switch that is activated to complete an electricalcircuit with a power source based on a conductivity or resistivity ofthe electrolyte solution.
 20. The toothbrush of claim 1, wherein themotorized device is a pump operatively connected to a reservoir andconfigured to deliver an active agent from the reservoir to outlets inthe head.
 21. A motorized toothbrush comprising: a head carryingcleaning elements; a handle including a cavity; a power source receivedin the cavity of the handle; a motorized device operably connected tothe power source; and electrical conducting elements operably connectedto the power source and the motorized device; wherein the motorizeddevice is activated upon exposure of the electrical conducting elementsto an electrolyte solution.
 22. The toothbrush of claim 21, wherein themotorized device is operably connected to the head to cause movement ofthe head.
 23. The toothbrush of claim 21, wherein the motorized deviceis a pump operatively connected to a reservoir and configured to deliveran active agent from the reservoir to outlets in the head.
 24. Thetoothbrush of claim 21, further comprising a switch operably connectedto at least one of the electrical conducting elements and the powersource to prevent electrical communication between the power source andthe motorized device or to complete the electrical circuit even withoutexposure of the electrical conducting elements to the electrolytesolution.
 25. A motorized toothbrush comprising: a head carryingcleaning elements; a handle; a power source contained within the handle;a motorized device operably connected to the power source and operablyconnected to the head; electrical conducting elements operably connectedto the power source and the motorized device; and a switch operablyconnected to at least one of the electrical conducting elements and thepower source; wherein the motorized device is activated upon exposure ofthe electrical conducting elements to an electrolyte solution having athreshold conductivity.